This Small Business Innovation Research (SBIR) Phase I project is in the general area of organic and macromolecular chemistry and in the subfield of organic synthesis. This research focusses on the development of efficient, chemical ways to introduce biotin into synthetic DNA fragments such that they can be subsequently detected with the streptavidin-alkaline phosphatase signaling system. This nonradioactive DNA hybridization probe has several advantages over the radioactive labeling techniques currently in use including much longer shelf life, greater convenience and safety, high detectability, and the capability for automated analyses. Such synthetic biotinylated oligonucleotides of mixed sequences can be used directly as hybridization probes for the rapid identification and isolation of specific genes. The sensitivity of the method for the visual detection of the hybridized probes is sufficiently high that 0.5 femtomoles of plasmid DNA should be detectable. The chemical synthesis of biotinylated DNA fragments will be carried out by the solid phase phosphoramidite method. The development of these biochemical probes should have significant impact on biomedical research and could find broad applications in the diagnosis of genetically determined conditions such as viral diseases and cancers. Whereas this Phase I activity focusses on oligonucleotides labeled with biotin, it should be possible to subsequently examine other types of nonradioactive labeling systems (e.g., fluorescent probes, electron spin resonance probes, photoaffinity labels) with potential applications in biochemical research.
